Paper shredding machine



July 10, 1934.

H. W. WILSON PAPER SHREDDING MACHINE Filed Feb. 24, 1931 Imam-1 Patented July 10, 1934 UNITED STATES PATENT OFFICE PAPER SHREDDING MACHINE Harry W. Wilson, San Francisco, Calif. Application February 24, 1931, Serial No. 517,908

8 Claims.

This invention relates to improvements in paper shredding machines.

An object of my invention is to provide an improved machine for tearing sheets of paper into a. number of narrow strips.

Another object of my invention is to provide an improved machine embodying a plurality of cooperating rotatable knives which are adapted to tear sheets of paper into a plurality of narrow strips.

A further object of my invention is to provide an improved paper shredding machine having a plurality of sets of rotatable discs which are capable of being adjusted so as to properly tear sheets of paper of difierent thicknesses into a plurality of strips.

A still further object of my invention is to provide an improved paper shredding machine embodying novel means for conveying sheets of paper into engagement with a plurality of cooperating discs which are rotatably mounted to tear the sheets into a plurality of strips.

Other objects more or less apparent will present themselves or will be specifically pointed out in the description to follow.

In the accompanying drawing:

Fig. 1 is a top plan view of a paper shredding machine constructed in accordance with my invention;

Fig. 2 is a side elevation of the same;

Fig. 3 is a sectional view of the shredder discs, showing their positions with respect to each other; and

Fig. 4 shows a fragmentary strip of the paper torn by the knives.

Referring to the drawing, the numerals 1 and 2 represent the spaced sides of a suitable supporting frame having a motor 3 mounted thereon. The sides of the frame are substantially of the same form and shape, and each is provided with two upwardly extending inclined projecting parts 4 and 5 which are separated one from the other by an intervening space. The inner adjacent sides of the projecting parts land 5 are provided with suitable slots or grooves within which projections-located on blocks 6 and 7 are slidably positioned.

Rotatably mounted within the blocks 6 and 7. respectively, are the ends of shafts 8 and 9, and each of said shafts have, respectively, a series of shredder discs 10 and 11 secured thereon. The discs are of circular shape and are provided with sharp double beveled edges at their peripheries. The discs of each series rotate with the shaft on which they are mounted, and by means, such as nuts 12, they are held in firm contact with one another. The discs 11 are so arranged with respect to the discs 10, that the beveled edges of the former are positioned between the beveled edges of the latter, with a slight clearance between. In order to adjust the clearance, so that different thicknesses of paper may be properly accommodated by the discs, a screw 13 having right and left hand threads is rotatably mounted between each pair of blocks 6 and '7, with the ends of the same extending into the said blocks. By turning the screws 13 in one direction the blocks 6 and 7 may be separated so as to separate the cutting edges of the two sets of discs, and when turned in the opposite direction the two sets of discs may be moved so their beveled edgesare brought toward each other. So as to adjust the positions of. the two sets of discs on the projecting parts 4 and 5 of the frame and without changingtheir relative positions, a screw 14 is rotatably attached at one end to each of the blocks 7, with its opposite end extending through and beyond a bar 15 secured to the ends of the said projecting parts 4 and 5. A nut 16 on each of the screws 14, serves as means for permitting the movement of. the 8 blocks '7 and 6, as a unit, either toward or away from the bar 15, thereby affording means for adjusting the positions of the discs 10 and 11.

The motor shaft is provided with a pulley 17 over which extends an endless belt 18, the said belt also extending over a large pulley 19 securely mounted on the shaft 8. The shaft 8 carries a gear 20 which meshes with a'gear 21 carried by the shaft 9, and thus upon the rotation of the motor shaft, the two sets of discs 10 and 11 may be rotated in opposite directions.

Rotatably mounted on the rearwardly projecting end of the frame and within suitable bearings provided thereon, are shafts 22 and 23, which carry, respectively, rollers 22' and 23'. An endless conveyor belt 24, extending over the rollers 22 and 23', is of sufficient width to accommodate sheets of paper to-be cut into strips. The roller 22 extends over and above the rear parts of the discs 10, thereby causing the sheets of paper delivered by the belt 24 to fall upon the said discs.

An end of the shaft 8 is provided with a gear'25 which meshes with an idler gear 26 mounted on the side 1 of the frame. The idler gear 26 is in mesh .with a gear 2'7 secured toan end of the shaft 22. Upon the shaft 8 being rotated as described previously, the roller 22' is rotated in a clockwise direction, thereby causing the endless conveyor belt 24 to be actuated in a direction 1 to cause paper mounted thereon to be carried toward the discs.

The sides of the frame 1 and 2 are each provided with an upwardly projecting guide 28 which is secured thereto as by bolts. Extending from one side of the frame to the other side thereof, are a number of bars 29 which act as safety means to prevent an operator from coming in contact with the beveled edges of the discs.

In operation, a number of sheets of paper or other suitable material to be torn into strips, are placed on the endless conveyor '24. The operator, after commencing the operation of the motor, guides the sheets so they fall into proper positions onto the discs 10. The rotating discs 10 carry the sheets into engagement with the beveled-edges of the two sets of discs 10 and 11, and the severing action of the latter tears the sheets into a plurality of elongated strips. The sheets of paper in passing between the two sets of rotating discs are torn into a plurality of strips which are each formed with a lengthwise crease therein.

The beveled edges ofone of the sets of discs being located intermediate but separated from the edges of the other set, enables strips of paper to be torn and creased in the manner illustrated in Figure 4. The sharp intermeshing edges of discs 10 and 11 cause the paper to be creased to form a fold, and the tearing thereof occurs when the discs are rotated at a considerable speed, at

points between the edge of one disc and the edges of the two adjacent discs. The speed of rotation of the discs causes the paper to be torn into strips, rather than cut by the sharp edges of the discs.

It is apparent to those skilled in the art that my improved paper shredding machine may be embodied in other constructions equally as eflicient as the one shown and described herein, so for this and other apparent reasons, I desire my invention included broadly within the spirit of the appended claims.

Having described my invention what I claim 1. In a paper shredding machine comprising a frame, a plurality of sets of rotatable bevelededged discs mounted on the frame, the cutting' edges of one set of discs being located intermediate and separated from the beveled edges of another set of the said discs, means for rotating the discs, and means for adjusting the position of either or both sets of discs, whereby the beveled edges thereof may be moved either closer to or farther from the .beveled edges of the other of said set of discs.

2. In a paper shredding machine, a plurality of sets of rotatable discs, the peripheries of which are provided with beveled edges, the edges of one set of discs being located intermediate the edges of another set a frame for supporting said sets of discs, the discs of one set being 'positioned'close to but separated from those of another set, means for adjusting the positions of the sets of discs, a conveyor mounted on the frame for conveying a material to the discs, and means for rotating the discs.

3. In a paper shredding machine, a. frame having a plurality of spaced inclined projections thereon, a plurality of supporting blocks adjustably mounted on and between the projections, a plurality of shafts rotatably mounted in the blocks, a plurality of beveled edged blades securely mounted on each of the shafts, the edges of those blades which are mounted on one shaft being positioned intermediate and separated from the edges of the blades mounted on another shaft, and means for adjusting the positions'of either or both of the blocks, whereby the edges of the blades on one shaft may be moved closer to or farther from the edges of the blades on another shaft, and means for rotating the shafts.

4. In a paper shredding machine, a frame having a plurality of spaced inclined projections thereon, a plurality of sets of supporting blocks adjustably mounted between and on the projections, a plurality of parallel shafts rotatably mounted on the blocks, a separate set of beveledged blades securely mounted on each shaft, the edges of those blades which are mounted on one shaft being positioned intermediate and separated from the edges of those blades mounted on another shaft, means for rotating the shafts and the blades, means for adjusting either or both sets of the blocks, whereby one of the shafts may be moved to change the relative positions of the edges of the -two sets of blades, and means mounted on the frame for conveying material toward the blades.

5. In a paper shredding machine, a frame having a plurality of spaced inclined projections thereon, a-plurality of blocks adjustably mounted between theprojections, a plurality of parallel shafts rotatably mounted on the blocks, a number of beveled-edged blades securely mounted on each shaft, the edges of the blades on one shaft being positioned intermediate and separated from the edges of the blades on another shaft, means for rotating the shafts and blades, means for adjusting the position of one of the shafts, whereby the edges. of the bladesthereon may be moved lcloser to or farther from the edges of the blades on another shaft, means for changing the positions of all of the shafts at one and the same time, and conveyingmeans for delivering a material to the blades.

6. In a paper shredding machine, a frame, a plurality of parallel shafts rotatably mounted on the frame, a set of beveled-edged blades securely mounted on each shaft, the edges of one set of blades being positioned intermediate the edges of another set of blades, means for adjusting the relative positions of the shafts whereby the edges of the sets of blades may be moved toward or away from each other, a conveying belt mounted on the frame and synchronized with the shafts for delivering material to the blades, and guides mounted on the frame near the belt.

7. In a paper shredding machine, a frame, a pair of oppositely rotated shafts mounted on the frame, each shaft mounting a plurality of bevel edged discs attached thereto, the discs of said pair of shafts intermeshing with their respective edge sides adjacent but not touching, means for conveying material to said discs, and means for adjusting the position of either or both of the shafts, whereby the relative postions of the discs may be changed.

8. In a paper shredding machine, a frame, a pair of rotatable shafts mounted on the frame, each having a plurality of double beveled edged discs fixedly mounted thereon, the beveled edges of the discs of one of the said shafts being positioned intermediate but separated from the beveled edges of the discs of the other of said shafts, and means for rotating the shafts.

HARRY W. WILSON. 

